Document Type : Research Paper
Author
Anbar University - College of Agriculture
Abstract
The study was conducted to specify the effect of three levels 0, 1,
2 S/Kg soil (S0, S1, S2)respectively of agricultural sulfur and two types of organic
substance (Manures) without adding CO and the dry powder of alfalfa C1 and
manures C2, added within the average of 6 grams C/Kg soil on the presence and
activity of minute photo autotrophic sulfur oxidation by an experience conducted
under laboratory conditions by utilizing silty soil achived under factorial
experiments of CRD design. All samples were incubated at 280 C for different
periods 15, 30, 45 days (T1, T2, T3) respectively. Activity and diversity of bacteria
related to types Thiobacillus of T. thioparus was estimated through measuring the
quantity of thiosulphate oxidation and the differences of values related pH at the
media specified for this bacteria.
The results showed that increasing the addition of agricultural sulfur has a great
effect (P<0.05) on increasing the density and activity of photo-autotrophic sulfur
oxidizing bacteria its number is 0.98*102 cfu/g and 1.31*102 cfu/g when adding
alfaalfa and cow manures respectively compared with 1.96*102 cfu/g on the control
treatment. Differences in incubation periods showed that 30 days is the highest level
of density 0.73*102 cfu/g. Interferences among levels of sulfur, organic substance
and incubation period showed that the highest level of (P<0.05) is 3.071*102 cfu/g
with treatment S1-CO T3. It was obvious that the soil utilized in the study was
containing oxidizing thiosulphate T. thioparus photo-autotrophic bacteria in wich its
activity increased with the treatment S1-CO T3. The amount of oxidation of
thiosulphate was 377 mg/100 ml, and the Ph at the media was 5.71. the soil utilized
was void of sulfur oxidizing bacteria.
Main Subjects
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